The Link Between NAD+ and Brain Aging

Food for Thought

Your brain is the hungriest organ in your body. At only 2% of your body weight, its main function—processing and transmitting information—consumes a full 20% of your body’s energy every day. 

Where Does All of This Energy Come From?

Think of mitochondria as tiny power plants that convert food and oxygen into energy inside your cells so they can do the job of powering your body. Now think of NAD+ (nicotinamide adenine dinucleotide) as the coenzyme that allows mitochondria to do their job by activating the enzymes that create energy.  NAD+ allows mitochondria to generate around 95% of the brain’s energy by making ATP (adenosine triphosphate). And just to give you an idea of how important mitochondria are to brain function, each brain cell has around 2 million mitochondria. 

Interesting mitochondrial fact:

Long before humans—0r even animals—evolved, one of the most important meetings in the history of life took place. A primitive bacterium, mitochondria, was engulfed by our oldest ancestor—a single, free-floating cell. The two fused and formed a relationship that has lasted more than a billion years, with the cell providing a comfortable home and the mitochondria  becoming a powerful generator, fueling life.

Most fascinating of all is that despite being integrated into our bodies, mitochondria carry their own DNA.

Mitochondria Cannot Function Without NAD+

Healthy mitochondrial function (and proper brain function, in turn) is intimately connected to the coenzyme NAD+.Without sufficient NAD+ levels, our mitochondria are not able to make the energy required by brain cells to survive and carry out their many functions. 

But NAD+ declines at the rate of 50% during adult aging. This may lead to less cellular energy, which can negatively affect cognitive function, and potentially lead to further brain health problems over time.

Proteins Are Also Dependent on NAD+ 

Sirtuins are a family of proteins that depend on NAD+ to function. Three of the sirtuin proteins are located in the mitochondria. Of these, sirtuin 3 (SIRT3) is known for its role in energy homeostasis (how our cells balance energy production and expenditure). SIRT3 also regulates ATP levels and is an important regulator of gene expression and enzyme activity. SIRT3 may protect mitochondria from stressors and promote biogenesis (new mitochondria). When NAD+ declines at the rate of 50% over 20 years, this has a negative effect on sirtuins as well. 

What Do Low Levels of NAD+ and Less Efficient Mitochondria Look Like in the Real World?

Along with all the other organ systems, the capabilities of the brain lessen with age. Brain aging (and actually, aging in general) can ultimately be defined as a decline in cell function. 

Brain aging, including low NAD+ levels and inefficient mitochondria, can manifest as deficits in learning, memory (both working and episodic memory), cognition, decision-making speed, and sensory perception. In fact, all five senses (vision, hearing, touch, taste, and smell) decline as a result of brain aging. Older people can have difficulty with word retrieval and understanding rapid speech. An aging brain may feel like exhaustion, depression, and brain fog. 

Even the brain’s appearance changes. It shrinks with age, beginning at around 30 years old and continuing with each decade. There is a reduction in gray and white matter. An enlargement of the cerebral ventricles along with thinning of the outer surface of the brain. These along with decreasing NAD+ levels lead to a slow decline in cognition.

During our sixth, seventh, and eighth decades, brain cells show signs of compromised mitochondria and NAD+ levels affecting neuroplasticity (the ability of the brain to change its activity in response to stimuli) and resilience. Molecules and organelles like mitochondria (an organelle is a subcellular structure that has a specific function, just like an organ in the body) may be changed by oxidation and inflammation. These alterations leave the brain vulnerable to potential problems.

The Good News About Brain Aging and Mitochondrial Health

There are plenty of things you can do to keep your mitochondria healthy and your NAD+ levels higher. 

Emerging findings show that sedentary, overindulgent lifestyles accelerate brain aging. And lifestyles that include intermittent bioenergetic challenges like exercise, fasting, and intellectual challenges foster healthy NAD+ levels and therefore healthy mitochondria. 

A nutritious, balanced diet is particularly important for mitochondrial health and NAD+. That means a diet high in quality protein, fresh fruits and vegetables, whole grains and nuts and seeds.These foods are a great source of B vitamins, antioxidants and healthy fats like omega-3s. Ultra-processed foods, sugar, and starchy carbohydrates impair mitochondrial function by triggering increased production of free radicals and causing oxidative stress. 

But what you eat isn’t the only thing to consider. You also need to be careful about how you eat. Overeating, or consuming more fuel than you need, creates harmful byproducts. And every time you ingest more energy than needed, you’re burning through your NAD+ supply and weakening mitochondria.  

Caloric restriction and intermittent fasting have also been shown to benefit mitochondrial health. Calorie restriction increases antioxidant defenses, which protect mitochondria from oxidative damage and age-related decline. NAD+ also increases and becomes active when faced with caloric restriction, triggering reactions that preserve mitochondrial health.

Finally, as we get older, exercise becomes even more important. Mitochondrial health and muscle function have been positively associated with higher NAD+ levels, demonstrating the positive impact of physical activity. NAD+ levels were also higher for those with more average steps per day. In other words, the more you move each day, the higher your NAD+ levels. So no matter how old you are, move if you can!

Supplements That Boost NAD+

Taking an NAD-boosting supplement is another way to combat cellular stress caused by poor diet, lack of exercise, excess alcohol, too much sun, too little sleep, and aging in general. 

By taking Tru Niagen® consistently each day, you can help protect your cells from the effects of aging. We all age. But we can choose to do so with higher levels of NAD+ and healthier mitochondria.